1. Field of the Invention
The present invention relates to an optical disk driving apparatus provided with a means for detecting a sector address.
2. Description of the Related Art
A general magnetic disk processor has a high reliability in operation since an error rate of a recording medium is low. Accordingly, there is no problem about recognition of an address recognizing section (an ID section) when data are written and read out of the recording medium. However, an optical disk processor has a high error rate of a recording medium so that an ID section cannot be recognized in a certain case. Therefore, processing efficiency is greatly reduced since the optical disk processor transmits information indicative of disability of writing and reading operations of data to a host processor, etc. To solve this problem, for example, an optical disk processor proposed and shown in Japanese Patent Application Laying Open (KOKAI) No. 58-215734 has means for recognizing a predetermined sector address indicative of a position of data in a format in which addresses are sequentially formed on an optical disk medium in advance. This optical disk processor further has means for recognizing sector addresses before and after the above predetermined sector address. When the above predetermined sector address cannot be recognized, but the sector addresses before and after the predetermined sector address can be recognized, the data are written and read out of the optical disk in accordance with the above format by sequentially judging the sector addresses before and after the predetermined sector address. Namely, if ID sections before and after an ID section (address recognizing section) of a specified sector can be recognized even when no ID section of the specified sector can be recognized, an address of the unrecognized ID section is detected by sequentially using addresses of the recognized ID sections. However, when the address of a certain sector is not recognized, it is necessary to confirm sector addresses just before and after this unrecognized address. Therefore, reading and writing processings cannot be performed while an optical head passes through the sector of the unrecognized address. The reading and writing processings can be performed after the sector addresses just before and after the unrecognized address are confirmed and the optical disk is rotated 360 degrees and the optical head again reaches the sector of the unrecognized address. Therefore, the general optical disk processor has a problem that processing speeds of the reading and writing operations are greatly reduced.
Further, in the general optical disk processor, it is necessary to make a pre-format in the ID section with respect to address information and an error detecting code so as to judge whether an address is correctly recognized or not. Therefore, in the general optical disk processor, redundancy is increased by the error detecting code so that a memory capacity of the entire disk is reduced.